package main

import (
	"fmt"
	"time"
)

type Rocket struct {
}

func (r *Rocket) Launch() {
	fmt.Println("Launch...")
}

func main() {
	r := new(Rocket)
	time.AfterFunc(3*time.Second, func() {
		r.Launch()
	})

	time.AfterFunc(3*time.Second, r.Launch)

	time.Sleep(5 * time.Second)
}
